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d.43 on Glow-worm Easicom 24

Your boiler is notifying you that its intelligent temperature control setting, known as the heating curve, has encountered a data error or needs to be re-adjusted.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Heating curve

From this model's manual
Verified against the Glow Worm Easicom 24 installation & service manual, page 26.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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